Electric furnace.



H. RGHLING W. RODENHAUSER.

ELECTRIC FURNACE.

APPLICATION FILED SEPT. 7. 190e.

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ELECTRIC FURNAOE. APPLmATIoN FILED SEPT. '1, 190s.

Patented Nov. 2, 1909. 2 SHEETS-SHEET 2.

HERMANN BCHLING AND WILHELM EODENHAUSEB, 0F VLKLINGEN, GERMANY,

ASSIGNOBS T0 THE GRNDAL A CORPORATION 0F GREAT BRITAIN.

KJELLIN COXPANY LIMITED. 0F LONDON, ENGLAND,

ELECTRIC FURNACE.

Speelttcation of Letters Patent.

Patented Nov. 2, 1909.

Application tiled September 7, 1908. Scrtl Ko. 333,686.

To al! whom it may concern:

lic it known that we, HEnnANN Rouuxc, munu facturer, and WILHELM RonnNnAUsnn. engineer, subjects of the German Emperor, reslding at Vlklingen-on-the-Saar, m the lhn ire of (ermuny, have invented new and use ul Improvements in and Relatingr to Electric Furnaces, ot' which the following is u specification.

T hc present invention relates to nn clertric furnace for converting iron into steel. inciting metals, obtaining metals from their ores, und for deoxidizlng und removing ases from molten iron and steel.

The furnace, in accordance with the nesent invention, in which the heating o the molten material is etlectcd by means of induced currents, differs from known induction furnaces in that the electric energy supplied to the primary winding is transmitted b induction to two or more groups of secon ary circuits, und thereby renders possible the use of large undivided surfaces und masses of metal without endangering the uniform lientin thereof.

Various forms o an electric furnace embodying this invention are represented in the accompanying drawings, in which Fi res 1 and 2 are horizontal and longitu inni section respectively of n double phuse furnuce' Figs. 3 and 4 are vertical und horizontni sections respectively of u spcciai development of the secondary winding; Fi 5 is u horizontal section of a single phase urnnce; und Figs. G und T ure horizontal sections of diti'erent forms of pol phusc furnaces.

Similar letters of refcrenctl refer lo si milm' )urls in ull views.

'l` te furnnce rcprcfwntctl in Figs. l und 2 routuins two groups of secondary circuits` the first group of which is forum-d hy the mutcriul to bc nn-ltcd itself. Huid mntcriul boing plucrd for this purpose in un nuuulur channel uround tho primary winding: l. Utuor more of those unnulur clmnnclsl ,-u1rrounds euch ieg of lin' trunsformcr. tht-rtlit-ing u rhnnnel for curls leg. This slm-Iting l rhuunrl in tritium-ll nl one or more plut-es. The furnucc muy lm so url'ungt-tl tlmt lay dividing the trunsfnrnnl' of u single pluis:- tmnucr, or hy using u lurulittI of trunstol-mers in u olyphusr luruucc tht` widening of the clmnncl, or sin-rolled smelling t t i henrth, u, lies between the transformers. 'lo raise the temperature in the smelting hearth, the current of the secondary circuit is short clrcuited through the charge ut this point. For this purpose one or more copper wire windings S are arranged between or over the primnry windings l" of each of thc transformer legs. The secondary winding S may also be located outside of the primary P, and furthermore, in order to economizc room, it may be conducted through pipe coils embedded in the masonry of the furnuce, water being passed through the pipesto cool the furnace wall und the primary coil. The secondary winding a of the two groups of circuits is suitably subdivided` to prevent the tendency of the charge to whirl.

rom the secondary winding the current is led as directly as possible to one or more le lates E on opposite sides of the smeltxng earth and in such manner that the direction of the current from pole plate to ole late corresponds to that directly inuce m the material iu the smelting chunnel. The pole plates nre connected to terminal plates e which are made of carbonaceous material or metal or tire resistant conductors or any suitable mixture of these, or on the other hund the pole plutc muy be molded in u mass which has the property of being nt the sume time both tire resistant und ood conducting, so that ut, this point the urnuce wull serves ns u conductor by which the secondary circuit is lcd to the mnteria] in the melting clntnnel.

The use of two groups of secondnry circuits mnkes possible the melting of larg(l undivided surfaces und masses of unite-rial with un exceedingly uniform healing thereof und ut. the snmr tin'u` servos to prevent the grunt dispcnsinn of tlul lines of torce which would tnke plnco if only the first group consisting of the melting clmnm-l cir cuitsl were employtul.

We rlnim :is our invention:

l. In un electric trnnsfornu-r furnucr, in romliinution u muguet rorc (r) piercing tln furnace und ln\\'ing r :t pritnur) :und n sto1ulury winding;` (p :mtl s). tlusmvlting room iu thc furmwc heilig formed by unnulul vluttnul (al) surrutnuliug tinmuguct voro.

.2. In nn clot-trio trunsl'ornu-r I'nrmnc, in romhinlltinn n muguet rort` tr) pien-ing tho l'nrmwo und tuning u prinmry :unl uwlmml ary winding (p and s), the latter being formed by a water pipe, serving as a cooling means for the furnace material, the smelting room in the furnace being formed by an annular channel (d) surrounding the magnet core.

3. In an electric transformer furnace. in

combination a magnet core (c) piercing the furnace and havin f a primary and a secondary winding 2 am x), the smelting room 1n the furnace lar channel (d) surrounding the magnet core, a portion of the channel (a) being widened to form a smeltinlr hearth and terminal lates (ggf) arranged within the sides of sai( smelting hearth, adapted to elecy lrically connect the seconda winding with the material within lsaid smc ting hearth.

4. In an induction furnace, a magnet core, a primary winding therefor and a melting channel surrounding said core, in combination with a secondary winding on said core and means for conveying,r the current induced in said secondary windin r to the melling channel to heat the materia therein.

In au induction furnace, a magnet core, a primary winding therefor and a melting channel surrounding said core, in combination with a sccondarv winding on said core and means for completing the circuit of the current induced in said secondary windin f throu h the material in the melting channel- 6. n an induction furnace, a magnet core, a primary winding therefor and a melting channel surrounding said core, in combination with a secondary winding on said core, terminal plates embedded in the aides of said melting channel and means to connect said plates to the secondary winding whereby the current nf the latter is completed through the material in the melting channel.

7. In an induction furnace, a magnet core,

icing formed hy an annun primary winding,r therefor und a melting channel surrounding said core, in eomhination with a secondary winding on said core, terminal plates embedded in the sides of said melting channel, a lire resistant conductor forming a protective facing for each of said plates, and means to connect said plates to the secondary windin l whereby the current of the latter is com cted through the material in the melting c xanncl.

8. In au induction furnace, a magnet core, a primary winding therefor and a melting channel surrounding said core. in the matei-inl in which channel the main current is induced, in combination with a secondary winding surrounding said core in which a current is induced by the electro-magnetic leakage of the furnace and means for convcymg the current induced in said secondary winding to the melting channel to raise thc temperature of the materials therein.

9. In an induction furnace a primary coil inducing a current in the material lo he melted and a leakage licld coil arranged with relation thereto nml means for conducting the. current induced in said leakage field coil to the inciting channel to heat the material therein.

lll. 'lhc combination with un electric transforl'ner furnace having a main ticld and a leaka e ticld, of a conductor arranged in the lea age field of the said furnace and means for leading the current induced therein to the melting channel to heat the material therein.

In testimony whereof we have signed our names to this specification in the presence of two subscribing witnesses.

HERMANN RCHLING. WILHELM RODENII AUSER. W itnesses:

Bassie F. Dumm', Louis VANnonN. ,l 

